1. Field of the Invention
The present invention generally relates to a system for utilizing air at substantially ground temperature for heating a building in winter and cooling a building in summer in a manner to reduce the use and cost of energy as compared to the use of conventional heating and cooling systems. The system of the present invention utilizes wall duct systems communicating a ground air inlet at the lower end of the duct system in a basement or the like with an outlet at the top of the building such as in the gable, along the ridge pole or the like so that gravity or thermal siphon flow of air will heat or cool the building.
2. Description of the Prior Art
The general concept of utilizing ground air to assist in heating or cooling a building is known and while such systems effect reduction in heating and cooling costs, certain of such systems have objections since the ground air utilized for heating or cooling is mixed with the air in the living space thus introducing questions regarding the purity of healthfulness of such air and, in some instances, requiring filters or other air treatment devices. The following U.S. patent relate to this field of endeavor but are not believed to be pertinent to the specific details of this invention:
U.S. Pat Nos. 1,974,244, Sept. 18, 1934; 2,119,038, May 31, 1938, 2,427,780, Sept. 23, 1947, 2,557,870, July 15, 1951; 2,793,509, May 28, 1957.